Back to EveryPatent.com
United States Patent | 5,668,559 |
Baro | September 16, 1997 |
The present invention concerns an antenna for portable radio devices including a helical antenna coupled at the base to a transmitter/receiver. The pitch of a conductive material helix constituting the helical antenna varies according to the height of the helix. It decreases from the base of the helical antenna towards its top.
Inventors: | Baro; Jose (Taverny, FR) |
Assignee: | Alcatel Mobile Communication France (Paris, FR) |
Appl. No.: | 322799 |
Filed: | October 13, 1994 |
Oct 14, 1993[FR] | 93 12226 |
Current U.S. Class: | 343/702; 343/752; 343/895 |
Intern'l Class: | H01Q 001/24; H01Q 001/36 |
Field of Search: | 343/895,702,749,901,752,841 |
2982964 | May., 1961 | Bresk et al. | 343/895. |
3283332 | Nov., 1966 | Nussbum | 343/895. |
3573840 | Apr., 1971 | Gouillou et al. | 343/895. |
3852759 | Dec., 1974 | Felsenheld et al. | 343/895. |
4121218 | Oct., 1978 | Irwin et al. | 343/895. |
4169267 | Sep., 1979 | Wong et al. | 343/895. |
4543581 | Sep., 1985 | Nemet | 343/702. |
4868576 | Sep., 1989 | Johnson, Jr. | 343/702. |
4890114 | Dec., 1989 | Egashira | 343/702. |
5317325 | May., 1994 | Bottomley | 343/895. |
5329287 | Jul., 1994 | Strickland | 343/895. |
5335366 | Aug., 1994 | Daniels | 343/702. |
Foreign Patent Documents | |||
0511577A3 | Nov., 1992 | EP. | |
810325 | Mar., 1937 | FR. | |
1183143 | Dec., 1964 | DE. | |
861229 | Feb., 1961 | GB. |